1. Department of Gene Function and Development, Roslin Institute, Roslin, Midlothian, Scotland, United Kingdom.
2. Instítuto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal.
3. Reproductive Technologies, AgResearch Ltd., Ruakura Research Centre, Hamilton, New Zealand.
4. Molecular Physiology Laboratory, The Wilkie Building, University of Edinburgh, Medical School, Scotland, United Kingdom.
5. MRC Technology, Edinburgh, Scotland, United Kingdom.
6. Centro de Estudos de Ciência Animal (CECA), Instítuto de Ciências e Tecnologicas Agrárias e Agro-Alimentares (ICETA), Campus Agrário de Vairão, Vairão, Portugal.